so-called hostile radiation belt force several months now collecting detailed measure manies of high energy particles and radio waves. eight years after it landed on mars, nasa's rover opportunity is still making discoveries. scientists announceed today at the american geophysical union meeting in san francisco that the rover has uncovered hints of clay mirals. they're important because they hold clues about the martian climate and should help scientists figure out if surface conditions could've been favorable for life. >>> the use of drones in war zones has stirred global debate. now an east bay law enforcement agency is drawing fire for its plan to launch a drone in their community. >> we should not be rushing headlong into buying a drone before the safeguards are in place, before the county has decided it should get a drone. >> american civil liberties union spoke out against the drone plan today just before the alameda county board of supervisors took up the issue. the sheriff hopes to buy an unmanned aerial system or drone using a state grant. it has hd video and infrared capabilities.